The present invention relates to an apparatus for flashing the turn signal lamps and display lamps of an automobile at an increased frequency when at least one of the turn signal lamps is disconnected. Thus, nearby automobiles are warned of the signal lamp malfunction and a potentially dangerous traffic situation is averted.
FIG. 1 illustrates a conventional apparatus for detecting a disconnection of a turn signal lamp which includes a flashing unit 25, a direction indicating switch 7, a display lamp 26, and a direct current power source 10. In normal operation, a current relay 8 provides discontinuous signal pulses to intermittently operate the signal lamps 2 and 3 or 5 and 6, respectively. However, when a signal lamp is disconnected, the relay 8 sends a continuous signal to the lamps and the lamps are thereby continuously operated to passively indicate the lamp failure condition.
The prior art has had difficulty in providing a simple circuit for utilizing the above continuous and discontinuous relay output signals to intermittently activate the signal lamps at an increased flash frequency to signal a disconnect condition. Indeed, even if the above discontinuous signal is integrated to produce the desired result, the output of an integrated constant level control signal is delayed.
Accordingly, it is an object of the invention to provide an apparatus for signaling a direction indicating lamp failure in a particular vehicle to the driver of the vehicle and other drivers in the near vicinity of the vehicle.
It is another object of the invention to provide an apparatus for signaling the disconnection of a direction indicating lamp by increasing the flash frequency of the lamp.
It is a further object of the invention to provide a simple, inexpensive and reliable disconnection indicating apparatus that is easy to manufacture.
These and other objects of the invention will become apparent from a review of the detailed specification which follows and a consideration of the accompanying drawings.